Green sea turtles have a variety of habitats however they prefer generally very shallow waters, such as bays and reefs. Many have their habitats along coral reefs. Sea turtles tend to live in three types of habitats during their lives. Young sea turtles spend their first 5 years in the open ocean. This can end up being quite dangerous for them as they are somewhat defenceless against larger predators. As the sea turtles start to mature they spend most of their time in very shallow water, mainly for the advantages in finding food, and escaping larger predators. Mature adults spend most of their time in lagoons and bays in generally tropical regions. Sea turtles only leave the water when it is time for a female to lay her eggs (this happens generally on beaches).
As illustrated by the dark blue areas in the map below, the green sea turtle prefers a tropical or sub-tropical area to call home, they normally spend their lives in the following oceans: Atlantic Ocean, The Gulf of Mexico, along the Argentine Coast, The Mediterranean Sea, and the Indo-Pacific region.
A map showing the distribution of Green Sea Turtles
The habitat of the green sea turtle is very important as they pick their habitats based on their ability to find food, and also for protection. The green sea turtle lives in very shallow water, so that they have good access to eat their food (marine grass and algae). Also their habitat is ideal as they are able to better protect themselves against their predators such as sharks who cannot survive in the shallow water. The animals may sometimes run into other sea creatures such as the Stingray, and when the young turtles are out at sea they would inhabit similar areas that Dolphin's do.
Green Sea Turtle Habitat
Adaptations
Structural Adaptation 1: The heavy shell
Sea Turtles are fortunate to have a strong shell protecting their body from harm. The shell is made from hard bone plates, covered by scutes (a bony external plate). The scutes are made of a substance called Keratine(a protein). The protein melanin adds the colour to the turtles shell. Although the scutes form the outer layer of the shell it is the bone underneath that provides the shape and the most protection for these sea turtles. The vertabrae of the turtle is very interesting as the vertebrates have formed to allow the animals to move more quickly through the water a very important quality to have. The shell provides excellent protection from the sea turtles predators such as large sharks and killer whales. The only drawback of this protective shell is it makes it much harder for the turtles on land as they become slow and more prone to land predators, because there shell is so heavy.
Structural Adaptation 2: The four flat limbs
Sea turtles have been constantly evolving to better adapt to their environment. One very useful trait that sea turtles and other turtles now have are their four flat limbs that have helped these turtles in significant ways. Firstly the flat shape of the four limbs allows the turtle to become more streamlined through the water which can protect them from predators, and they can cover more ground in less time. As well as being streamlined the limbs are not quite as heavy as their thick shell as previously discussed, allowing the turtles faster movement on all four limbs. The curved shape of the sea turtles limbs somewhat resemble that of a propellor or paddle which allows the turtle to move faster because their is more force exerted by the turtle, and the limbs act like a blade cutting through the water. While these limbs are an asset for the turtle in the water, the turtle is limited to their use on land as the turtle cannot use them fully due to the heavy shell and therefore the turtle becomes more slow and prone to attack from land predators.
Advantage of Flat Limbs
Behavioural Adaptation 1: Female lays her eggs always on the same beaches
When a female turtle is ready to lay her eggs she always returns to beaches where she has laid her eggs before, or perhaps where she was born. The sea turtle is not the only creature that does this. Other animals such as the salmon return to the river where they were born to lay their eggs. This behavioural adaptation might have occurred to prevent the female turtle from getting lost and allowing her to lay her eggs on time. The downside of laying her eggs on the same beaches every year is that many other turtles may have laid their eggs in the same area and unintentionally the female may dig up another turtles nest and destroy the eggs beneath the sand. Another growing problem is in some countries where many sea turtles lay their eggs humans dig them up and serve the eggs as a delicacy. Humans also may destroy the eggs as we consume more of the sea turtles habitat. Other animals such as raccoons will notice the nest and try to dig up the eggs to eat. The amount of danger these eggs and their mother are put in has lead to the decrease in population of many turtles and sea turtles.
Behavioural Adaptation 2:Lays eggs above the high water mark
The female sea turtle lays her eggs in beaches normally high above the high water mark. This has allowed the young turtles more of a chance of being protected from sea predators like sharks but it has not protected them from land predators such as raccoons. The turtle may have behaviourally adapted this way in order to keep the species alive however with more human threats to the turtle population this animal may have to adapt to protect their eggs.
Physiological Adaptation: Design of the green sea turtles lungs
The lungs of the green sea turtles are designed for rapid air exchange. The sea turtles lungs are highly elastic as they have cartilaginous supports (secondary bronchi) that extend deep into the lung. These features allow the turtle to breathe deeply without the collapsing the airways. This adaptation has allowed sea turtles to become excellent breath holders which is important to all marine animals. Without these important adaptations it is very likely that the Green Sea Turtle would not be able to spend as much time under the water, and baby Sea Turtles would not be able to spend their first few years in the open ocean.
Click on the this link to learn more about Odontochelys (Ancestors of the Sea Turtle) : Ancient Ancestor
Click on this link to learn more about The Future Sea Turtle : Future Green Sea Turtle
Classification of the Green Sea Turtle:
Habitat
Green sea turtles have a variety of habitats however they prefer generally very shallow waters, such as bays and reefs. Many have their habitats along coral reefs. Sea turtles tend to live in three types of habitats during their lives. Young sea turtles spend their first 5 years in the open ocean. This can end up being quite dangerous for them as they are somewhat defenceless against larger predators. As the sea turtles start to mature they spend most of their time in very shallow water, mainly for the advantages in finding food, and escaping larger predators. Mature adults spend most of their time in lagoons and bays in generally tropical regions. Sea turtles only leave the water when it is time for a female to lay her eggs (this happens generally on beaches).
As illustrated by the dark blue areas in the map below, the green sea turtle prefers a tropical or sub-tropical area to call home, they normally spend their lives in the following oceans: Atlantic Ocean, The Gulf of Mexico, along the Argentine Coast, The Mediterranean Sea, and the Indo-Pacific region.
The habitat of the green sea turtle is very important as they pick their habitats based on their ability to find food, and also for protection. The green sea turtle lives in very shallow water, so that they have good access to eat their food (marine grass and algae). Also their habitat is ideal as they are able to better protect themselves against their predators such as sharks who cannot survive in the shallow water. The animals may sometimes run into other sea creatures such as the Stingray, and when the young turtles are out at sea they would inhabit similar areas that Dolphin's do.
Adaptations
Structural Adaptation 1: The heavy shell
Sea Turtles are fortunate to have a strong shell protecting their body from harm. The shell is made from hard bone plates, covered by scutes (a bony external plate). The scutes are made of a substance called Keratine(a protein). The protein melanin adds the colour to the turtles shell. Although the scutes form the outer layer of the shell it is the bone underneath that provides the shape and the most protection for these sea turtles. The vertabrae of the turtle is very interesting as the vertebrates have formed to allow the animals to move more quickly through the water a very important quality to have. The shell provides excellent protection from the sea turtles predators such as large sharks and killer whales. The only drawback of this protective shell is it makes it much harder for the turtles on land as they become slow and more prone to land predators, because there shell is so heavy.
Structural Adaptation 2: The four flat limbs
Sea turtles have been constantly evolving to better adapt to their environment. One very useful trait that sea turtles and other turtles now have are their four flat limbs that have helped these turtles in significant ways. Firstly the flat shape of the four limbs allows the turtle to become more streamlined through the water which can protect them from predators, and they can cover more ground in less time. As well as being streamlined the limbs are not quite as heavy as their thick shell as previously discussed, allowing the turtles faster movement on all four limbs. The curved shape of the sea turtles limbs somewhat resemble that of a propellor or paddle which allows the turtle to move faster because their is more force exerted by the turtle, and the limbs act like a blade cutting through the water. While these limbs are an asset for the turtle in the water, the turtle is limited to their use on land as the turtle cannot use them fully due to the heavy shell and therefore the turtle becomes more slow and prone to attack from land predators.
Behavioural Adaptation 1: Female lays her eggs always on the same beaches
When a female turtle is ready to lay her eggs she always returns to beaches where she has laid her eggs before, or perhaps where she was born. The sea turtle is not the only creature that does this. Other animals such as the salmon return to the river where they were born to lay their eggs. This behavioural adaptation might have occurred to prevent the female turtle from getting lost and allowing her to lay her eggs on time. The downside of laying her eggs on the same beaches every year is that many other turtles may have laid their eggs in the same area and unintentionally the female may dig up another turtles nest and destroy the eggs beneath the sand. Another growing problem is in some countries where many sea turtles lay their eggs humans dig them up and serve the eggs as a delicacy. Humans also may destroy the eggs as we consume more of the sea turtles habitat. Other animals such as raccoons will notice the nest and try to dig up the eggs to eat. The amount of danger these eggs and their mother are put in has lead to the decrease in population of many turtles and sea turtles.
Behavioural Adaptation 2:Lays eggs above the high water mark
The female sea turtle lays her eggs in beaches normally high above the high water mark. This has allowed the young turtles more of a chance of being protected from sea predators like sharks but it has not protected them from land predators such as raccoons. The turtle may have behaviourally adapted this way in order to keep the species alive however with more human threats to the turtle population this animal may have to adapt to protect their eggs.
A video of a bay sea turtle entering the Ocean: Baby Sea Turtle Going Out to Sea
Physiological Adaptation: Design of the green sea turtles lungs
The lungs of the green sea turtles are designed for rapid air exchange. The sea turtles lungs are highly elastic as they have cartilaginous supports (secondary bronchi) that extend deep into the lung. These features allow the turtle to breathe deeply without the collapsing the airways. This adaptation has allowed sea turtles to become excellent breath holders which is important to all marine animals. Without these important adaptations it is very likely that the Green Sea Turtle would not be able to spend as much time under the water, and baby Sea Turtles would not be able to spend their first few years in the open ocean.
Defenders of Wildlife (2010) Sea Turtles. Retrieved from http://www.defenders.org/wildlife_and_habitat/wildlife/sea_turtles.php Retrieved June 22 2010
Sea Turtle.Org, . (2010). Global sea turtle network . Retrieved from http://www.seaturtle.org/ Retrieved June 21 2010
Turtle, Puddle. (n.d.). Anatomy of the turtles shell. Retrieved from http://www.turtlepuddle.org/health/anatomy.html Retrieved June 23, 2010
Sea World, . (2002). Sea turtles. Retrieved from http://www.seaworld.org/infobooks/seaturtle/stlongevity.html Retrieved July 1 2010
Sea World, Initials. (2010). Sea turtles- adaptations for an aquatic environment. Retrieved from http://www.seaworld.org/animal-info/info-books/sea-turtle/adaptations.htm Retrieved July 3 2010
Wyneken, Jeanette. (2001, July 13). The Migratory behaviour of hatchling sea turtles beyond the beach. Retrieved from http://www.arbec.com.my/sea-turtles/art13julysept01.htm Retrieved June 24, 2010